Search found 14 matches

by Larry Woods
Tue Mar 30, 2004 10:02 am
Forum: General Discussion
Topic: extra displays for register
Replies: 0
Views: 1654

extra displays for register

Hi everyone,<p>I'm playing with an old TEC cash register for educational purposes to see if I can add extra displays off the unit to put in different locations.The register has an display on top of the unit for people to view. Has anyone done this before? I suspect the displays may need their own po...
by Larry Woods
Tue Jan 06, 2004 3:05 pm
Forum: General Discussion
Topic: volts,amps, watt question
Replies: 2
Views: 2089

volts,amps, watt question

on a wall transformer it might read output 3.9 volts dc and 420 mamps out put and 120v/6.7 watts input. On a resistor the ohms are givwn with a watt rating ie 1/4 watts.<p>Is the watt rating mean the maximum you can put through it?? For a wall charger does that mean thats a limit it will deliver and...
by Larry Woods
Wed Dec 10, 2003 5:17 pm
Forum: General Discussion
Topic: WHITE LED FLASHLIGHT
Replies: 8
Views: 4271

Re: WHITE LED FLASHLIGHT

I'm interested in lighting up a number of these LED's and was wondering how many I could put in Parallel ( correct ????) to get more light. Not concerned on longevity(assume a bigger battery) but more on circuit handling the load.<p>Thanks people
by Larry Woods
Tue Oct 21, 2003 10:19 am
Forum: General Discussion
Topic: electric fence
Replies: 9
Views: 4031

electric fence

I'm having a problem with Racoons ripping up my roof. I want to put up an electric fence like on a farm that stops cows roaming everywhere. It should pack a punch but not be lethal.<p>Can I get some advice on how to build the supply?<p>Many thanks
by Larry Woods
Tue Aug 19, 2003 9:03 pm
Forum: General Discussion
Topic: induction heating effects on conductor
Replies: 2
Views: 2892

induction heating effects on conductor

I have recently done inspection on building electrical distribution and found some securing rings over heating because of eddy current action. Does anyone know if other than the heating if the current carrying conductor is affected over long terms. ie years.<p>Thanks
by Larry Woods
Thu Jul 31, 2003 8:03 pm
Forum: General Discussion
Topic: Buying a digital multimeter
Replies: 16
Views: 7596

Buying a digital multimeter

I've been using an analog version for some time and want to buy a digital voltage meter ( multimeter). What features should you look for and are there any recommendations without spending a big dollar?<p>Thanks
by Larry Woods
Wed Jul 30, 2003 8:10 pm
Forum: General Discussion
Topic: WTB for friend: Cheap 12V 20A supply
Replies: 10
Views: 5834

Re: WTB for friend: Cheap 12V 20A supply

Just curious as I read these posts to try get a feeling of the process. Your statement of isolating 2 of the grounds to avoid shorting out to ground puzzled me somewhat. <p>Is there more than one common ground and a relativity thing?<p>Thanks
by Larry Woods
Tue Jul 15, 2003 8:21 pm
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Re: Ni Cad chargers help

Thanks Denny,<p>You're right, reinventing the wheel isn't the plan but originally I couldn't find a charger with the specs I thought I needed. <p>Since I've learned a lot, even how tought it is to package the items in a decent finished state.<p>I will look up the completed package, but is rat shack ...
by Larry Woods
Thu Jul 10, 2003 9:15 pm
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Re: Ni Cad chargers help

I have the parts for the slow charge project except the power supply is 16 volts /300. This was the closest I could get at the store. Is this acceptable. Is it like resistors where you get close?? <p>Do I need to to changes. How do you know what tolerences are acceptable???<p> Thanks<p>Larry
by Larry Woods
Mon Jun 30, 2003 1:40 pm
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Re: Ni Cad chargers help

Thanks,<p>I'm off to get the parts I don't have presently. I'll build the unit you suggested and as I get the parts Scott suggested Ill try a quick charge version.<p>Thanks to all and I'll let you know how I make out.<p>Regards,<p>Larry
by Larry Woods
Sun Jun 29, 2003 5:54 pm
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Re: Ni Cad chargers help

The advice Scott gave is excellent and am reading about it. Fast charging isn't critical to me and the direction you suggested might me easier for me. If you could give me that information I'd like to try starting that way.<p>Thanks,<p>Larry
by Larry Woods
Sat Jun 28, 2003 9:12 pm
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Re: Ni Cad chargers help

From yours and the earlier post replys I have been educated a lot. On closer inspection, the battery pack is a Ni MH with a 2000 mah rating and is a 7.2 volt battery( 6 cells). It can be charged quickly with a 8.7 volt/ 1.4 amp charger output. I realize now that the charging methods for different ba...
by Larry Woods
Sat Jun 28, 2003 11:16 am
Forum: General Discussion
Topic: Ni Cad chargers help
Replies: 15
Views: 9151

Ni Cad chargers help

My friend wants to build an 8.7 Volt 1.4 amp charger for a ni cad battery. I said I would help him but I only know a little more than him which is "just a little" We talked about using a LM 317 T chip and circuit that Russ K. suggested for voltage regulation. Are we on the right track or s...
by Larry Woods
Sun Jun 22, 2003 3:00 pm
Forum: General Discussion
Topic: voltage regulator
Replies: 3
Views: 2204

voltage regulator

I want to have a 6 volt( sometimes a 1.5 or 3.0 volt) supply off a 12 volt battery.The 12 volt supply is required for a 12 automotive sensor while the lower voltages are for an electronics package. What should I use as I understand a resistor only isn't acceptable.<p>Help is appreciated.<p>Thanks, L...